Concn of caustic lye, by spraying lye into vessel - at constant temp and pressure, so water is removed as steam

摘要

Process for removing water form aq. solns. of alkali lyes. The novelty is that the initial soln. is directed in a fine spray onto the surface of a lye possessing the desired final concn. in a heated zone in which the pressure and temp. are adjusted to the equilibrium conditions for desired final concn., and steam and the final lye are removed from the zone. The amt. of lye employed with the final desired end concn. in the zone is pref. min. ten times the wt. of steam removed per hour, and max 30 times this wt. of steam. The ratio of the height of lye in the zone to the dia. of the surface of the lye is pref. between 1:1 and 1:8. Continuous water removal from alkali hydroxide solns. obtd. e.g. from the electrolysis of being to mfr. Cl and alkalies, using a smaller amt. of plant requiring less labour, maintenance and repair, and with better energy yield.